Field of the Invention
The present invention relates to a tunnel boring device used in the excavation of a tunnel, and to a method for controlling this device.
Background Information
The excavation of a tunnel is performed using a boring machine equipped with a cutter head including a cutter at the front of the machine, and grippers provided on the left and right sides at the rear of the machine.
This boring machine excavates the tunnel by pressing the rotating cutter head against the working face in a state in which the left and right grippers have been pressed against the left and right side walls of the tunnel.
Japanese Laid-Open Patent Application H10-131664, for example, discloses a control device and a method for controlling a redundant parallel link mechanism equipped with jacks that exceed the number of degrees of freedom, wherein the proper control can be performed even if the number of control devices is reduced.
With this redundant parallel link control device, eight or more thrust jacks are provided to give redundancy to position and direction control of the forward section while resisting external force during excavation, and stroke control hydraulic circuits are provided to six of these thrust jacks. With the remaining thrust jacks, the pushing side and pulling side thereof are made to communicate with the hydraulic circuits on the pushing side and pulling side of the thrust jacks that are stroke controlled. This reduces the size of the control hydraulic devices.